RACOM M!DGE3, Руководство пользователя

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4.2. Antenna installation
The type of antenna best suited for the individual sites of your network depends on the layout of the
network and your requirements for signal level at each site.
The antenna should never be installed close to potential sources of interference, especially electronic
devices like computers or switching power supplies.
Additional safety recommendations
Only qualified personnel with authorization to work at heights are entitled to install antennas on masts,
roofs and walls of buildings. Do not install the antenna in the vicinity of electrical lines. The antenna
and brackets should not come into contact with electrical wiring at any time.
The antenna and cables are electrical conductors. During installation electrostatic charges may build
up which may lead to injury. During installation or repair work all open metal parts must be temporarily
grounded.
The antenna and antenna feed line must be grounded at all times.
Do not mount the antenna in windy or rainy conditions or during a storm, or if the area is covered with
snow or ice. Do not touch the antenna, antenna brackets or conductors during a storm.
4.3. Antenna feed line
The antenna feed line should be chosen so that its attenuation does not exceed 3 to 6 dB as a rule of
thumb. Use 50 Ω impedance cables only.
The shorter the feed line, the better. If M!DGE3 is installed close to antenna, the data cable can be
replaced by an Ethernet cable for other protocols utilizing the serial port, see
Section 7.1.3, “Terminal
servers” .
Always follow the installation recommendations provided by the cable manufacturer (bend radius, etc.).
Use suitable connectors and install them diligently. Poorly attached connectors increase interference
and can cause link instability.
4.4. Grounding
To minimize the odds of the transceiver and the connected equipment receiving any damage, a safety
ground (NEC Class 2 compliant) should be used, which bonds the antenna system, transceiver, power
supply, and connected data equipment to a single-point ground, keeping the ground leads short.
The M!DGE3 radio modem is generally considered adequately grounded if the supplied flat mounting
brackets are used to mount the radio modem to a properly grounded metal surface. If the radio modem
is not mounted to a grounded surface, you should attach a safety ground wire to one of the mounting
brackets or a screw on the modem’s casing.
It is strongly recommended to install an appropriate lightning protection system where the antenna
cable enters the building.
M!DGE3 Cellular Router – © RACOM s.r.o. 30
Installation